The present invention relates to a method and an apparatus for, as one process of manufacturing individual zippers or slide fasteners formed of a fastener chain comprising a pair of opposed tapes carring interlocking teeth or elements of plastic filament coils, removing a certain length of the interlocking teeth from the slide fastener chain, whereby a sequence of the "space sections" which are devoid of the interlocking teeth are provided at predetermined intervals in a lengthy continuous slide fastener chain.
In order to simplify and facilitate the assembling and finishing of zipper fasteners, it nowadays is a common practice of the manufacturers to work on a single, continuous slide fastener chain consisting of a pair of opposed stringer tapes carrying thereon uninterrupted rows of continuous interlocking elements, rather than on separate, individual fastener chains, and then to provide element-free sections or the so-called "space sections" in the continuous fastener chain at predetermined intervals for mounting sliders and end stops and thereafter to cut the thus treated length of the chain at each space section to produce the individual zipper fasteners.
In the manufacture of the slide fasteners of the coiled plastic filament type having a lengthy, continuous slide fastener chain, there have been proposed various methods and apparatuses, in particular, for removing a certain length of interlocking elements from the slide fastener chain. However, none of them have been found completely satisfactory, since the removal had to be conducted only by excessive force and tended to injure the fabric tape to which the interlocking elements are attached.
The removal of the interlocking elements in accordance with the prior art techniques was conducted by a combination of at least four steps as follows: (a) step of securedly supporting the fastener chain in a position where cutting step (c) is to be carried out, (b) step of exposing the head portions of the interlocking elements out of the opposing edges of the carrier tapes to an extent at least that the carrier tapes should not be impaired by cutting in the subsequent cutting step, (c) step of cutting off the exposed head portions by means of a cutter or a punch, and (d) step of removing the leg portions of the interlocking elements or the element debris by pulling out of the sewing threads. (See, for example, U.S. Pat. No. 3,852,869.)
The above-mentioned four steps have had to be carried out one by one, each after completion of the preceding step, resulting in low working efficiency, and the apparatus used was an assemblage of individual parts functioning for each of the steps, whereby the apparatus has no more been simplified.